Question
Question: (a) An x-ray tube produces a continuous spectrum of radiation with its short wavelength end at 0.45....
(a) An x-ray tube produces a continuous spectrum of radiation with its short wavelength end at 0.45.what is the maximum energy of a photon in the radiation?
b) From your answer to (a).guess what order of accelerating voltage (or electrons) is required in such a tube?
Solution
An x-ray tube which converts the input electrical power to x-ray. X-ray are types of radiation which are called electromagnetic waves. X-ray is penetrating from high energy electromagnetic radiation. X-ray imaging creates pictures of the inside of your body. The images show the internal bones are parts of our body in black and white shades.
Complete step-by-step solution:
An X-ray tube is an electrical device containing two principle elements cathode and anode. When an electric current is supplied to a tube an electric current flows from cathode to anode , then the electrons lose their energy which results in the generation of X- radiation. In anode X-radiation is produced the quality of X-ray produced can be controlled by adjusting the electrical quantities.
X-ray tube is an energy converter which converts electrical energy into two other forms that is X-radiation and heat.
Energy of photon is inversely proportional to wavelength of light and is given by the equation
E=λhc ⋯⋯(1)
Where, h = Planck’s constant
c = speed of light
λ = wavelength
X –ray has wavelength which ranges from 10−8 to 10−12 meters
From the data we known the value of short wavelength(λ)=0.45×10−10m=45×10−12m
c=3×108 And h=6.62×10−34
On Substituting this values in equation (1)
E=45×10−126.62×10−34×3×108E=0.44×10−14JE=1.6×10−190.44×10−14E=0.275×105eV
E=27.6×103eV
The maximum energy of photon is 27.6keV
Maximum energy is equal to the peak accelerating potential of the X-ray tube.
Accelerating voltage is responsible for the production of x-ray by providing energy to the photons in order to get an X-ray of 27.6KeV the electron has to possess a minimum27.6KeV of kinetic energy.
So an accelerating voltage of 30KeV is necessary or required to produce x-rays.
Note: Students this problem is solved by using the formula of energy of photons and photons which do not have mass(rest).X-rays are produced by stopping high energy electrons in a tungsten target. Maximum energy is equal to peak accelerating potential of the x-ray tube and x-rays are scattered within a material.